Visible evidence of poor air quality appeared in satellite imagery of California on November 18, 2007. The Moderate Resolution Imaging Spectroradiometer (MODIS) flying on NASA’s Aqua satellite captured this image of haze in southern California, in the San Joaquin Valley. In this picture, the dingy gray haze occupies the southern end of the valley, just east of the Sierra Nevada.
A November 18, 2007, posting on the U.S. Air Quality-Smog Blog at the University of Maryland, Baltimore County, described poor air quality in California in the days prior to this image acquisition.
NASA image courtesy the MODIS Rapid Response Team at NASA GSFC.